SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '190970a8742e1a8ca9dd47e933ba6ff0f40798d53c15c12beabc4027c0520db1' 
  AND token = 'CZw1Ca5V+vtlAP9iC1A8QsdXDvDOJIVVKN4I2cIa+9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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