SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41471d1354ad4b09034e6fb75633aba8461cd792fce81ed9fd1144e5133324af' 
  AND token = 'wtD5j40oN1hz2/F//rt8x7USDKNVpOhcMf5ZAgjZKLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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