SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0caf0430190823adbc9624f442abb6f6070d939c64db45eee8d19eb0d606149' 
  AND token = 'Dc5s87Zaz+SyYBX0tauksOyIsUcHfH0Ad4YAPntLf+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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