SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74a92ea201d8bb2a39f1e1dc3528d4236864f9db12fefe4013384ea3f95994c5' 
  AND token = 'WY7LZ5syqcgGSAKnu+lfdJQH2NpYSos9Ovmf2FB4QRs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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