SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2029d5508c4e45706ba783ab21acba619e4379698357323a809246c6a97d163c' 
  AND token = 'mA+4qVmKieZgQBMpLIIkzY8JfYEf33j/AMv5qYtTElo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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