SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae466e549ea7ce5af12fb6f0227876896f289ea0522d1496c22d0629bff7d90a' 
  AND token = 'ZWVFvcICYqwyKQ+1G93YawTmqoinQlc+G7hk/INic1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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