SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '136d406ec982560e941030f595438ccaea2f2956d1e57172ca9733b0751aabcf' 
  AND token = 'Ea7DhLailqRY2u+XYYhZ/J4q6GxtNqPaByNXb6xLPSg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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