SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18222961c24cd63177e2566122849465307c5ab42131febb83b5df9ca2914ed3' 
  AND token = 'e+e0zPmk2aTFyjIqVRtVJXypJANgavGWtrMHIKm4Fo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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