SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3dd3eb4bf653880148fb7b4c0386c2e8eaeb98b60bdc704c3bdc65dadd36a0e' 
  AND token = 'Y+MPbV27G7wiXiYZA9SbrjeokyyXZJ1R4U3kB1QwDYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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