SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8eea5db9f1e21f5ad23601b70133da2def9b1f75693d6a394ebaed82d7aca2be' 
  AND token = 'oTEGXa3FscXrbnBMq4/lZBeY8BXA9qphV4cTBfoNzUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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