SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6afa00d361a59640fd5817fb03fc70ecc95c25f2647d1bf8ccf0dc365c6820d8' 
  AND token = 'rnAqs2GQ5FEGlym+tNKnHj124NwDAdGe+aQdzd/T/YI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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