SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16fa2ff2018a38390c032146aa0b34d1b5f8b323e58d97ae137c1bb1482019b6' 
  AND token = 'P6vQPpqnTamsYhRix8yKQ+wtFkc1YXZzVa8XXNJ/b1c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}