SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f9e58a0eb09ba62b314eaa6fa515f4afda0082bac431ddbbe57951bbe882562' 
  AND token = 'vkil5pMICOMI6e7GmeRFBMbq/pcwYWaVk1uUAfVFS90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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