SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8813646007f741a8c6c175ad2cafb2977f8ff95406e548089b0a954f992942b7' 
  AND token = 'rrgw102nlsAefC7FDqgXnomHFlMPk79FGYZYwzE0ITo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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