SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c1a3e7bbca52f7baa4c26e9b129290c542c9c25e24db2a03d9d097060f69092' 
  AND token = 'RMrbUuRk0Q7rOD1eIxVRAdGCZSrK7HCqqxIQ55Gziuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}