SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17594f5ebdd7ae1c6fbf2e5db7b58052b839e72d25a70fd386c69b7111be13c6' 
  AND token = 'pTB5shoUO2pvQaHgH65lufnYHyOz5Z/VyT8qiLPjF+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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