SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4ee312366eff33120bb557a5ed920f2329f53141f4e6da419da87b8efdac3be3' 
  AND token = 'sDqunqPWvfgJCHc6wS2F0W0UR2SohKaRFrymCQtYznQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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