SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58faf6793d98d67997cb46cb23f2859c21942c0b44f2b95bb8b854bfa1318426' 
  AND token = 'sBxKkXUW6Im/+NLRTpuDOCwmYSyCUy9XbYY8vq0G7r0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}