SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0abea243856a8e02458f2eaa17b3aaab880b118b2dbbfab9e064e52518d4ad98' 
  AND token = 'KBm4RdkLY6WhdSct3hZuFckPBCEZh5NY+BcpnOdvdWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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