SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a918bf30c6d30e4ea41fc6f14c1a15f0d56590816252055f067ba869b3e23e2a' 
  AND token = 'cLG38AvC4Gemi5opfzZjXq1sbyYm4tvxOvSPtuk5ykA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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