SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7219da04b02c7b45f0f0510818467f832516866953a18ce3088066d90a1c6470' 
  AND token = 'zJ9kscFak2dbogm6dhKZQJCa2RvmTKB3jwp39Q7GfRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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