SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fe3a800259b3e98160bf489eb705be192d222df7ffae7fcf23182c7876b05a2a' 
  AND token = '+A7tygKqqaQycGsVxg6Q4c2nPAXqZq2dCmZeFlydQrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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