SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c29dd34681594241bb071a9356df67a977064cff8bbc744563455d32b9280495' 
  AND token = 'gyGNWIjJaI/n2IjJG/MBitBtOlkUQlTWfZDb2uf8GCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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