SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0f733b147b04352516c05b3077fb8fd2edfe9946658c431f6005d253ebe3a3b' 
  AND token = 'sChoa/Pf+gXVGw5M0f2hSKj5XKZHUzLV7FkI03ZDCiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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