SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e2dd8c94b8d6f538eb224a1d472f282ea141dce77a9a8dada413c1a788d3209' 
  AND token = 'AR1hxqrk6WoPZZ+9N0kyjdN+roP16yX/1zUNHzLtCzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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