SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ef592f1f8b9ce25c57f211cfe2bdccc95facbd86e4b869007ed9864770613cd' 
  AND token = 'TZBK/6Ngqgc+BiMLUssrK2uGdRSkWFp/sEuIjqmizTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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