SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1731712f7fb4ab9bfdc313d6ff8358e9d95972d3058a898fba964d60cd55c9a' 
  AND token = 'YFFcX6vJvmuYy+cT7PVP6wASLBsaGDy5XxOo/kreRXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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