SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02fd5b9adc8977de312cfd8190e64f1dd492271ca6dbf59707e86a3b7d5ee8a5' 
  AND token = 'z00GYMwkqqdURB/Rn/pFfmwguqAj8nwkjGjKlctn1qg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}