SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a572fd2acbe20ef1b904a700040409e74f8c2d7f1d0bade9a64dbaa129d711ed' 
  AND token = 'jA1UClLQtN8zfksXMwVzagV8+YxouPTzyvDlnULIVAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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