SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d7421666c0a7da1d467e61e53ba3769d154d920e5b0edd2193313e20360b362' 
  AND token = '2FP+eXGen5dJAn05Y1zgilL5asuuvJ7IbfCF+qS8CBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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