SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '396ee4981bd6477362498ef176c7e0e0399aa39f1ff65e6ce26c6ba38237d62b' 
  AND token = 'zMH7bopiJl417p+YacPjS5SHdv5FPZE3IXuFhJqL9Fg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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