SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ded49037f29dd8116a60e44a2cf4e066937808634d9546ee81a1591572521784' 
  AND token = 'UAFhTCOBKpDitEmiaZOYDVX7TjeJVgV/uhHW7QiYEFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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