SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0d906ada8139f943277b38ce18d0bbc27dead3ddabb3f9ee637312892546648' 
  AND token = 'f23sr+MgMSFRchiSxYKNcLFAun9iMcvgKHdLKAygH6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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