SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cff906d9e1208a8b0086b88a8cc63622e94e1188016d3d7a63931d0f42ca0fb' 
  AND token = 'oaKEGdPJeH88iPT1x3FqzLCB5JBoSjU1ph2RFs3HocY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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