SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecb0a63822fffc4439fbaf1163605452a09e7f0dc8f967b461470c1f71397c58' 
  AND token = '3SO3nEcc9kKI2GGnkus/bwSed2iFJoUMyLKMa5S/WkA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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