SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ceaf8773c686d0c8bbed14af475210bd3cb8d33a24f1172fa5532d9c641b8f9' 
  AND token = 'GqutGRRaGnoqLn3jJVu0jrLpuZOvjNObMb/Ed2HIh0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}