SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b0cabcc21906e63beb04f29ec395567ce3c817270792560f6e07620b88155c3' 
  AND token = 'cdGuUfvqRcpWxEU6ablME06oCMh50rJmJ8UyemVpS7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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