SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e5488e212eafaa54cac5569101a5bfb94c38aa99ea34b0165043590d4552336' 
  AND token = 'dX94ckESh4VgQLRvVzNrzUY1DdUYFvcAu10a7Gktnzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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