SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2bcb6a12ad7e689842d33d06ca429fa24652da447a90d73e4a075f703a172ae' 
  AND token = 'RzZuDiroiqT4stOiLZR4CVEUk8orw1+iedytnCmRyok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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