SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32661f8a78991e51d9aa50054e5094341b5956a916cef15940a9823da6656f2c' 
  AND token = 'APSzsdZF7uenozadOfkE+YRcxSVMBoUUq8eSJ5CfyWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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