SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f224ca6c553309e7a4437991238f0a78444d6026eb416f8b0f76c448245bf7c0' 
  AND token = 'e2Jgo/lQvDfkaAlpQmBhHnAoZP7COgJluUfVHBFsoyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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