SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d5670250c9338b61152f1a8b7b365488ad92a290d651ec43348f895bffa710e' 
  AND token = 'Cz5WyAZ2u16foxdrQt0yB/2isb0htzVPZlaRKmzVBSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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