SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd693057274f29231d46a86711ab44789ac2778d07d142446d698dab973d3b776' 
  AND token = 'tZ4n3V77nJOgcGbbOKRLxLvONfoSQmHm6sZMYlIfuuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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