SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ca6618d1cb3f2cbc964a67f4b58af23294bc5c1a4f0457aae01195d295d49ac' 
  AND token = 'TaDIAofHfzLyl1HMu0IMBcLpvD6O/7Y3BjELBGBQWqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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