SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3679be80638b8d39c1e0d6ebb4a09a1aca917a4a1c0f57bec3b11a2e6ab46d1b' 
  AND token = 'tTHD0Yy2rEMH9gIOL7Q5wF3K0AZBd2xw1w/LyWhokp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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