SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aef19c07daf45686f7728773d7090ee9f8b0c1e19f414a609cbdfdb4a0b58ae3' 
  AND token = 'dVzM6n711khpxZHVvShBEbVt1I+lBj+6Lg6ONzKuY14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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