SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e58b3f9086a02440116a9d442d1dd4b3117161ad60abf1fb3c8fc2d958c4aab6' 
  AND token = 'SgP3a/LVgY97rHhDgXkoSw7gMkKlpe3EvlpDvK6zx+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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