SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b13178c77e8af95ad1f0b052b7e81ba2c310da4963126299dbdbbfbdce115619' 
  AND token = '65o+BtyBwlRRkCqbwDI+Tded7jfB6tjQ1qxlIvl6lFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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