SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2082edd8426f1819ded88623a401f7463889d3be75b193338b623c58caa5537' 
  AND token = '/MEZRhA0UjAW1sm+yTJNO8D1Pjz8MDFzckEVSJ4cqJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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