SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d5bfe775167089d4c24ff631345430e01e93db9e92cdb6e7f9bf4571a851595' 
  AND token = 'Hot36C4XPqgK3TGRpjlh/v/uIV6ga2aaMk0OZq+ys/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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