SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0effd7f61b7d3f86ea6886062a2e6b9748580897889d70545c3dfa9dee7f998b' 
  AND token = 'Qa9tfII1ulmHOjnBlia3/grANeQO5lxi9ifquyGemzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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