Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1a3ddf9575b5f99ad102c5ad5ce2e54a0e7f6153476aa7971d825aba2529a10' 
  AND token = 'DDT0Q0KWtGCl6BYLh9QsfkEqi3CZRoeUG/kGv/RCZvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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