SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f9459728c59e2b2fd6eddba0930f546846e9ef57107edef4ce59527630a598b' 
  AND token = 'H8MYuG7nBtihKjUwCgdU+S0pO5UV2/JWDbwbJD/47VQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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