SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '027aeca5cdf86d3e7d695ee35fc3b8029d4f89169739cdccf5f638e307ffcc41' 
  AND token = 'BY/rDxYuRNYExYivBcE4/Rz4qWbqxStOb61fbjlLyIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00093

JSON explain

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