SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d587125ae3dc7a5a5f9e7074885a1a4cc10fd6ca32ffd2897b0d29024123755' 
  AND token = 'DdwckR3LW3vXJ8vWi1wYOhnGEyE/QmGMh9G+uTFucAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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