SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b20fe2eb1869194a18b185ecb5b34730054cca23ec6cd0382007f9258c64c3ce' 
  AND token = 'Ik4VeEwDPhD6+djmL17M55kL+p389eVQ6Lq5iewybEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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