SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2e46fc34425f8c69c82810749e6e489442384de676d33297de2c54374e7fdbe' 
  AND token = 'LRPlurBTsjZ+S/tZI7ruJjQk4+VSSvkycViggXHvK/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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