SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc14fc2298e607773e632a65d7bc8c0993db2ecc1ed6b127974e42c96b33b7e9' 
  AND token = 'N0cgBoONEmxRLUXmW8slrVpiRDANlsVdLw3OmyzEzdE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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