SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee20d06a0f8b0dc2fee48e7d8329475892c3693d3b95b92815195a6fe393825b' 
  AND token = 'rWr3kpSbNgwMK4cPSJQSB3k8OhP43YUIJCHliH4kAGk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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