SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '359e6f66a93b6439b0681f39778457c012b2995223ef4018b05a1cefff9d67bf' 
  AND token = 'tBZJvDZkNyPFjJRfyn/DQXkfhnQTYvN0iwqzCDpdmV8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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