Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a51f4f20be56a053bb41aae5faa74fbe0f48d39a95cd0b776ba1bbfe302dc110' 
  AND token = '5zUXw2Kx5KUjFTVU/qdby6UYHyR2rdvzne/66FDz/kI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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