SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd834bb58c75042f7c79b1971090595d93323ce12a97036e931e23491fe6ff671' 
  AND token = 'XdFzIOuBZP4JP+8DrEL4pycfAOApNChGXs7RHBudkeY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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