SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'efc4d79a8f57af7d381dd46ce648f15bab9e25f9a3c2cd40a81975aefd596d6b' 
  AND token = 'eXeUR3mwuclKEKIq1nD3hEgDXC2qxhg9APj9Y+q7zBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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