SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f01e25d4898c7de09acb099310bb35fdfcb988d4c7a470af9df849504b0f9a9a' 
  AND token = 'nRlNffEgRHvpg9IVBPYgRZeReZkbF978nPbZK38cdM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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