SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14c8af36a7d34eab9a46c8394c41cda3b2051ff1721b736bfe21fc381d6db324' 
  AND token = 'hlqTUmB7S04OzD3g2QreHf+vZR/PAAdB/Gsmjy2j4zI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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