SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90d8ec692cad270a70300d57be41d62c87f46310dcdf4fcf2bd59114d5501710' 
  AND token = 'fTk09sZV0f+WXcyVjnTKc1G3T6VlI4s6fxAlsADXT6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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