SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e356a595a019a975073b697b128660f85b686eac447a0cf2a5d25482db2d24e7' 
  AND token = 'P3wjT84eLXzOWi84sY/hNXTaB3+O7RsDLepUrX/KyiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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