SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0381dd1e39d0584ceb518d878b1638ce0bbef6c9c8af1d920b1c2ee4b644b06a' 
  AND token = 'IEI/drxFPHJJ7UqfLEyq64dypfRg4ICbEZd+wutF5Dw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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