SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55e1b961ffe3457778cecedd82e20622a9e8de994991b2f58c4d849f84474849' 
  AND token = 'W/HOQghqfsw7oQr0K/U0WGumHiKB21KJPXTslEDY+iY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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