SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5eb7572fe645188d7fa9f9a52d2e2ffbca56142933f583aa97705239a6f68bed' 
  AND token = 'BfIADXxTVCpg6nmoDlWKqhUytXERrS6VbLJxuzYEtjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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