SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85b8432a95a86aee3fb243746ba216455d4f477004ea2758880ec9406458b38d' 
  AND token = 'L5VeHsygHI6qbF/tRrTYLCCXks80nNGbyWKNhE57ifs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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