SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f777624bc5cffface42e4925629437a40cbb0353fa99b87d70cf64932ba736c9' 
  AND token = 'y04o6z+nnjxOmN0x+zRoUot6VXk/LXHyFE7Eaq5TzJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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